21971125 has 48 divisors (see below), whose sum is σ = 32610240. Its totient is φ = 14616000.

The previous prime is 21971119. The next prime is 21971129. The reversal of 21971125 is 52117912.

It is not a de Polignac number, because 21971125 - 2¹³ = 21962933 is a prime.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21971093 and 21971102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21971129) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 757611 + ... + 757639.

It is an arithmetic number, because the mean of its divisors is an integer number (679380).

Almost surely, 2^21971125 is an apocalyptic number.

21971125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21971125 is a deficient number, since it is larger than the sum of its proper divisors (10639115).

21971125 is a wasteful number, since it uses less digits than its factorization.

21971125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103 (or 64 counting only the distinct ones).

The product of its digits is 1260, while the sum is 28.

The square root of 21971125 is about 4687.3366638209. The cubic root of 21971125 is about 280.0812901729.

The spelling of 21971125 in words is "twenty-one million, nine hundred seventy-one thousand, one hundred twenty-five".